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The AIVC was created in 1979 and started having annual conferences in 1980. The 2019 Conference was its 40th conference and the conference theme focused on its anniversary. This Technical Note is a compendium of the contributions that the AIVC has made in its first 40 years and reflects field’s evolution over time. Much of the information generated by the AIVC is of direct use today and some of the older material is good source material for future research.The AIVC is an information dissemination project created by the International Energy Agency (IEA) as a result of a need to understand the energy impacts from air leakage in buildings for the energy crisis of the 1970s. When the Center was first created it was called the Air Infiltration Center because the focus was on energy loss due to infiltration. It was generally thought that most buildings leaked way too much air and that reducing that infiltration would reduce dependence of fossil fuels.The mechanism the IEA uses to create projects is through implementing agreements of member nations. The AIC was the 5th project (or “annex”) created by the implementing agreement on buildings and community systems, which has been renamed Energy in Buildings and Communities (EBC) at https://www.iea-ebc.org/. There have been 70 projects completed from EBC and 17 that are on-going currently. Of those, Annex V is the only information dissemination center and the only one that is active for more than a few years.Because infiltration research was not a field of its own in the 70s, the AIC became the de-facto coordinating body for infiltration-related research around the world. It was sometimes difficult to understand each other, hence we started a series of TN named AIRGLOSS [36] in which terms and definitions were described. When investigating a new area, the first thing one must do is be able to measure it. A significant effort was put into measurement techniques both for air change rate and for air tightness. The research community is much broader now, but these are still active areas of research. Chapter 3 discusses air tightness and Chapter 4 discusses air flow measurement techniques.Infiltration and air tightness are of course related, but quantitatively connecting air leakage and air flow, requires modeling and such models did not really exist. So along with a focus on measurement techniques, the AIC worked on infiltration modeling as discussed in Chapter 5. The first models were simple, physical models, but as computing power and the state of knowledge grew, so did the models.After only a few years, it became clear that looking at infiltration in isolation was a sub-optimal approach. As buildings were getting tighter, there was a concern of insufficient air exchange. An optimal energy solution would then need to include both infiltration and designed ventilation. Accordingly, annex V’s mandate was broadened to include ventilation systems and in the mid-80s the name was changed to the Air Infiltration and Ventilation Center as it remains.In 1985 the AIVC began publishing technical reports (e.g. TN 17) [12] that specifically focused on optimal ventilation strategies. Many AIVC (and conference publications) have worked this problem in the last 35 years. Chapters 14 and 15 review many of the approaches used today. One of the more recent trends is to make our ventilation systems smarter and Chapter 13 looks at some aspects of that.It was also realized during the 1980s that occupant behavior had a bit impact with respect to ventilation overall. EBC Annex VIII focused on this and resulted in 1988 in AIVC TN23[15] on the topic. Early research focused on issues such as window opening, but later work looked at how mechanical systems are perceived and ran. Chapter 10 looks at occupant impacts from today’s perspective.Ventilation for acceptable indoor air quality generally uses energy to condition the outdoor air, but there are times when ventilation can save energy, if it displaces the need for mechanical cooling. Providing ventilative cooling can be through both mechanical and natural means and can positively impact comfort. Chapter 8 discusses these issues.As the AIVC was going to work on optimal ventilation strategies, it was important to know what the standards for acceptable ventilation were and this became another focus of the center’s work. The center has published many documents related to standards such at TN26 in 1989 [17] that summarized EBC Annex IX. Ventilation standards have grown much more sophisticated since those times and are addressed in Chapter 9.One thing common to most ventilation standards over that period is that they assume that outdoor air is clean, or at least substantially better than indoor air. In such a case one can use it to dilute indoor-generated contaminants without worry. We know that in many cases this assumption is wrong, but it is not always clear what to do. Chapter 12 looks at the issue of outdoor air more broadly.Outdoor air contains moisture, but water vapor is a rather unique kind of contaminant: it has both an indoor and outdoor source and we neither want too much of it nor too little. Control of moisture has been a priority for the AIVC since it had a workshop in New Zealand (TN20) in 1987 [13]. Chapter 7 provides an overview the issue today.Another unique kind of constituent is carbon dioxide. CO2 is a product of combustion including human metabolism and therefore is unavoidable in indoor spaces. At high enough concentrations CO2 can become deadly, but it is not a contaminant of concern in typical buildings. It is, however, a good indicator that can be used in ventilation systems. Use and misuse of CO2 is a quite topical issue today. Chapter 11 discusses the role of CO2 in buildings.Since the turn of the century, it has been clear that the purpose of ventilation is acceptable indoor air quality and one cannot determine acceptable indoor air quality without looking at health. A growing part of the more recent efforts of the AIVC have been focused on understanding this health linkage and optimizing systems accordingly. Chapters 6 and 13 address what the AIVC has been doing in this area and form a basis for future activities.

In 2006, the Energy Performance Certificates (EPC) were implemented in the Swedish national building code. At the same time, the energy use demands in the building code (BBR) were transformed to be only performance based, i.e. a demand only on the maximum energy use. The country is divided in four climate zones, with the highest allowed energy use in the north and the lowest in the south. The EPCs are based solely on the measured energy use in the building. The regulation requires that the measured energy use is corrected to normal use during a reference year. However, there is no standardised methodology to account for normal use in the EPC and this is therefore seldom done. This study is focused on investigating the cause of differences between the calculated and measured energy use in buildings, in order to detect compliance problems with measured EPCs. Based on interviews, analysis of two databases with EPCs in single-family houses and multi-family buildings, complemented with energy use calculations, potential general procedures and parameters that cause these differences are identified and investigated. Suggestions on improvements to the Swedish EPC scheme are also presented. For new buildings, the regulation requires that the energy use is calculated and presented for the municipality in the building permit application. This calculation is most often based on early design drawings where limited knowledge is available on the technical properties of the building. Previous studies have shown that the variations on energy use caused by the occupants’ behaviour is often underestimated in energy use calculations. In single-family houses, differences in the occupants’ behaviour can account for up to 50% of the building’s energy use. In low energy houses the variation of the occupants’ behaviour has a larger relative impact on the energy use than for buildings with higher energy use. To rule out the possibility of failures in the construction and operation of buildings, the building process needs to be followed by measurements at regular intervals of e.g. airtightness. However, these measures are not enough to guarantee an energy use in line with calculations. Not only the occupants’ behaviour, construction and operation influence the measured energy use. It is also influenced by the location and number of energy use meters for heating, domestic hot water and facility electricity. For example, a previous study showed that unexpected heat losses in culverts in the heating distribution system increased the energy use in a multi-family building by 12.6%. Similar results were also described in the interviews. Two energy and climate advisors and two energy experts were interviewed in this study. They are involved in different stages of the design of buildings and follow-up of energy use in buildings. According to Boverket, around 90-95% of all the buildings sold in Sweden have a valid EPC. The regulation also requires that all new buildings have an EPC two years after commissioning. There are no national studies performed on this topic in Sweden to the knowledge of the authors. The municipalities cannot legally force a home owner to supply them with an EPC and there are no sanctions if the regulation is not fulfilled. The home owner is often reluctant to pay the fee for an EPC and instead waits until the house is put on sale on the market. In this study, 100 single-family houses were expected to have a valid EPC since 2 years passed after commissioning. However, the number of EPCs was 44 which means 44% compliance with the current regulation. This is problematic since the energy experts do not get the feedback needed to improve calculation procedures and input data. In larger construction projects, an energy coordinator is often appointed to follow up changes in the design and their influence on the energy use. For single-family houses this is rarely done. There is no formal certification or knowledge needed to submit an energy use calculation for a building permit application. However, there are guidelines and standardised input data available for energy use calculations. Even though the calculated energy use corresponds well with the energy use reported in the EPC, the calculation can be wrong, caused by erroneous allocation of the energy supply and energy demand, making comparisons unfeasible. Wrong data on e.g. efficiency of ventilation heat exchangers, thermal bridges and losses from circulating hot water circuits could rule out e.g. the influence by occupant’s behaviour. Analysis of a database containing the calculated energy use for 313 single-family houses built since 2009 in the municipality of Lerum revealed that there was no tendency for calculations targeting 4 Sweden - Differences between Measured and Calculated Energy Use in EPCs versus Building Permits the maximum allowed energy use. The most common heating system was an air to air heat pump followed by ground source heat pump. For 80 houses in the database, information on the heated floor area was available. This data showed that the energy use per square meter was lower for larger buildings. The floor area also influences the difference between the calculated and measured energy use which is higher in percentage for smaller buildings. The information on energy use, floor area, household electricity and hot water use in the calculation and EPC report were compared for six of the buildings in the database. The analysis showed that there are large deviations on which data is used and how it is obtained for the different buildings. For instance, non-compliant heated floor area was reported where the garage erroneously was included in the EPC report. For one of the houses, detailed numerical analysis were performed where 54 occupant scenarios were studied. The energy use varied between 39 kWh/m2 to 73 kWh/m2 compared to 26.6 kWh/m2 in the calculation report and 39 kWh/m2 in the EPC. This illustrates the importance of a methodology for correcting the energy use to normal use. The dispersion in energy use in buildings with different heating systems was analysed using a database of 1,753 EPCs for buildings in the metropolitan Gothenburg area. Both single-family houses and multi-family buildings were analysed. The energy use is influenced to a larger extent by the choice of heating system than by the choice of ventilation system. As discussed above, it is important to use the correct heated floor area and attribute the energy use to its correct demand and supply in the calculations. In many cases, the heated floor area was transformed from other sources than direct measurements in the building. The heated floor area was obtained by direct measurements in 63% of the multi-family buildings and in 100% of the single-family houses. The domestic hot water and facility electricity was allocated based on experience, and not measurements, for a majority of the buildings. The main conclusions of this study are that: - Energy use by occupant’s behaviour explain a large part of the difference between calculated and measured energy use. - Normal use is not standardised and therefore not accounted for in the EPC. - Few buildings have energy meters that separate energy use for heating from energy use which should not be included in the EPC, e.g. household electricity. - Bad compliance of the number of EPCs reported for new buildings 2 years after commissioning is caused by lack of follow-up actions. To improve the EPC scheme and quality of energy use calculation, further work is needed in the area of standardising input data, calculation procedures and reporting of EPC.

The energy use in buildings is dependent on the choices made during the design, construction and renovation. The causes for these differences are, among others, caused by the behavior of the occupant of the building and the choice of heating and ventilation system. The European scheme of Energy Performance Certificates (EPCs) aims at reducing the energy use in the built environment. It is most common to calculate (i.e. not measure) the energy use for the buildings which are affected by the scheme. In Sweden, on the other hand, the EPCs are normally based on measurements of the actual energy use in the building. This makes comparisons between calculated energy use for building permit and measured energy for EPCs possible. In this paper a study of the differences between the calculated and measured energy use and its correlation with the choice of heating and ventilation system is presented. This is done by detailed investigations of the calculated and measured energy use in 44 buildings. For further analysis, a database of 1 753 buildings with measured energy use (EPCs) is used to study the dispersion in energy use for buildings with different heating and ventilation systems. Analysis using numerical simulations tools on human behavior has also been performed. The results of the investigation can be used to further improve the measured EPCs.

Politicians and scholars often frame schooling as one of society’s most important crime preventive measures. The object of the study is to examine and problematize the hopes and ambitions that have evolved around what the study conceptualizes as the crime preventive educational task of public schooling and its historical trajectory as articulated in government publications. Drawing on governmentality theory, the study focuses on the liberal conception of the autonomous and self-regulating subject, and how the liberal mode of government works through the governing of freedom. The study identifies three discourses on crime preventive education: The emancipatory (1970s onwards), the deterrence (late 1980s onwards) and the safety/security discourse (21st century). The discursive shifts identified are further analysed in respect to how i) the explanation of crime, and the relationship between the deviant and the law-abiding subject, ii) control and iii) freedom and responsibility, are conceptualized over time. The conceptualization of criminal behaviour goes from being caused by social deprivation, becoming instead a calculated rational act. Subsequently, the deviant is altered from a person in need of reintegration to a deterrent example and a risk. The problematization of control has a trajectory from being a matter of social control and integration, ending instead as a matter of risk control and prudentialism. The conceptualization of the kind of freedom and responsibility the crime preventive education should foster is also reframed, from a strategy to counter a lack of democracy and influence, to a way of making prudent citizens. In this, the notion of a collective responsibility has been superseded by a belief in individual responsibility. The key problematization vindicating the process has gone from how to integrate youths into a society in constant flux, to how to restore control if lost and how to protect a pre-given social order.

Politicians and scholars often frame schooling as one of society’s most important crime preventive measures. The object of the study is to examine and problematize the hopes and ambitions that have evolved around what the study conceptualizes as the crime preventive educational task of public schooling and its historical trajectory as articulated in government publications. Drawing on governmentality theory, the study focuses on the liberal conception of the autonomous and self-regulating subject, and how the liberal mode of government works through the governing of freedom. The study identifies three discourses on crime preventive education: The emancipatory (1970s onwards), the deterrence (late 1980s onwards) and the safety/security discourse (21st century). The discursive shifts identified are further analysed in respect to how i) the explanation of crime, and the relationship between the deviant and the law-abiding subject, ii) control and iii) freedom and responsibility, are conceptualized over time. The conceptualization of criminal behaviour goes from being caused by social deprivation, becoming instead a calculated rational act. Subsequently, the deviant is altered from a person in need of reintegration to a deterrent example and a risk. The problematization of control has a trajectory from being a matter of social control and integration, ending instead as a matter of risk control and prudentialism. The conceptualization of the kind of freedom and responsibility the crime preventive education should foster is also reframed, from a strategy to counter a lack of democracy and influence, to a way of making prudent citizens. In this, the notion of a collective responsibility has been superseded by a belief in individual responsibility. The key problematization vindicating the process has gone from how to integrate youths into a society in constant flux, to how to restore control if lost and how to protect a pre-given social order.

Med ikrafttrædelse af lov om bekæmpelse af ungdomskriminalitet i 2019 introduceres en ny tænkning i dansk strafferet, der betegnes som social-strafferetlig. Børn og unge mellem 10 og 18 år bringes under visse forudsætninger ind i de nyoprettede ungdomskriminalitetsnævn, hvor de påtvinges sociale hjælpeforanstaltninger. Hvis de er fyldt 15 år er det en forudsætning, at de er dømt for kriminalitet. Hvis yngre, er det alene en forudsætning at de er mistænkt.